server/filter/KeyManager.java

/* 
 * i-scream central monitoring system
 * http://www.i-scream.org.uk
 * Copyright (C) 2000-2002 i-scream
 * 
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * of the License, or (at your option) any later version.
 * 
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 * 
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
 */

//---PACKAGE DECLARATION---
package uk.org.iscream.cms.server.filter;

//---IMPORTS---
import uk.org.iscream.cms.server.util.*;
import uk.org.iscream.cms.server.core.*;
import uk.org.iscream.cms.server.componentmanager.*;
import java.util.Random;
import java.util.HashMap;

/**
 * Acts as a store and checking mechanism for host keys.
 *
 * @author  $Author: tdb $
 * @version $Id: KeyManager.java,v 1.3 2002/05/18 18:16:02 tdb Exp $
 */
public class KeyManager {

//---FINAL ATTRIBUTES---

    /**
     * The current CVS revision of this class
     */
    public final String REVISION = "$Revision: 1.3 $";
    
    /**
     * The set of characters to be used for our keys
     */
    private final char[] KEYSET = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789".toCharArray();
    
    /**
     * Default key length
     */
    public static final int DEFKEYLEN = 15;
    
//---STATIC METHODS---

    /**
     * Return a reference to the single class.
     * Construct it if it does not already exist, otherwise just return the reference.
     */
    public synchronized static KeyManager getInstance() {
        if (_instance == null){
            _instance = new KeyManager();
        }
        return _instance;
    }

//---CONSTRUCTORS---
    
    /**
     * Private constructor to avoid external construction.
     */
    private KeyManager() {
        try {
            String keylen = ConfigurationProxy.getInstance().getProperty("Filter." + FilterMain.NAME, "Filter.KeyLength");
            _keylen = Integer.parseInt(keylen);
        }
        catch (PropertyNotFoundException e) {
            _keylen = DEFKEYLEN;
            _logger.write(toString(), Logger.WARNING, "No key length found, using default of " +_keylen+ " : " + e);
        }
        catch (NumberFormatException e) {
            _keylen = DEFKEYLEN;
            _logger.write(toString(), Logger.WARNING, "Malformed key length found, using default of " +_keylen+ " : " + e);
        }
    }

//---PUBLIC METHODS---
    
    /**
     * Add or replace a key.
     *
     * @param host the hostname to add a key for
     * @param key the key to add
     */
    public synchronized void addKey(String host, String key) {
        _keys.put(host, key);
    }
    
    /**
     * Check if a given key is currently valid.
     * Will respond negatively if the key doesn't match,
     * or if no key is found (and EnforceHostAuth is on).
     *
     * @param host the hostname to check the key for
     * @param key the key to check
     * @return whether the check was successful
     */
    public synchronized boolean checkKey(String host, String key) {
        Object o = _keys.get(host);
        if(o != null) {
            // if our key isn't null, we want to make
            // sure it matches that given
            String ourKey = (String) o;
            return ourKey.equals(key);
        }
        else {
            // default to enforcing host auth
            boolean enforceHostAuth = true;
            try {
                // try to get see what's in the config
                String enforce = ConfigurationProxy.getInstance().getProperty("Filter." + FilterMain.NAME, "Filter.EnforceHostAuth");
                enforceHostAuth = (Integer.parseInt(enforce) == 1);
            }
            catch(PropertyNotFoundException e) {
                // if it's not set, not enforced
                _logger.write(toString(), Logger.WARNING, "EnforceHostAuth property not found: " + e);
                enforceHostAuth = false;
            }
            catch(NumberFormatException e) {
                // if it's not a number, not enforced
                _logger.write(toString(), Logger.WARNING, "EnforceHostAuth property malformed: " + e);
                enforceHostAuth = false;
            }
            // if enforceHostAuth is true we want to fail the check
            // and vice-versa
            return !enforceHostAuth;
        }
    }
    
    /**
     * Generate a random key with length KEYLEN.
     *
     * @return a random key as a String
     */
    public String genKey() {
        Random r = new Random();
        StringBuffer s = new StringBuffer();
        for(int i=0; i < _keylen; i++) {
            s.append(KEYSET[r.nextInt(KEYSET.length)]);
        }
        return s.toString();
    }
    
    /**
     * Overrides the {@link java.lang.Object#toString() Object.toString()}
     * method to provide clean logging (every class should have this).
     *
     * This uses the uk.org.iscream.cms.server.util.NameFormat class
     * to format the toString()
     *
     * @return the name of this class and its CVS revision
     */
    public String toString() {
        return FormatName.getName(
            _name,
            getClass().getName(),
            REVISION);
    }

//---PRIVATE METHODS---
    
//---ACCESSOR/MUTATOR METHODS---

//---ATTRIBUTES---
    
    /**
     * This holds the current keys for
     * the hosts we're authenticating
     */
    private HashMap _keys = new HashMap();

    /**
     * The length of our keys
     */
    private int _keylen;
    
    /**
     * This holds a reference to the
     * system logger that is being used.
     */
    private Logger _logger = ReferenceManager.getInstance().getLogger();
    
    /**
     * This is the friendly identifier of the
     * component this class is running in.
     * eg, a Filter may be called "filter1",
     * If this class does not have an owning
     * component,  a name from the configuration
     * can be placed here.  This name could also
     * be changed to null for utility classes.
     */
    private String _name = FilterMain.NAME;

//---STATIC ATTRIBUTES---

    /**
     * A reference to the single instance of this class
     */
    private static KeyManager _instance;

}
Revision:	1.4
Committed:	Tue May 21 16:47:17 2002 UTC (22 years ago) by tdb
Branch:	MAIN
Changes since 1.3:	+3 -2 lines
Log Message:	Added URL to GPL headers.
#	Content
1	/*
2	* i-scream central monitoring system
3	* http://www.i-scream.org.uk
4	* Copyright (C) 2000-2002 i-scream
5	*
6	* This program is free software; you can redistribute it and/or
7	* modify it under the terms of the GNU General Public License
8	* as published by the Free Software Foundation; either version 2
9	* of the License, or (at your option) any later version.
10	*
11	* This program is distributed in the hope that it will be useful,
12	* but WITHOUT ANY WARRANTY; without even the implied warranty of
13	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14	* GNU General Public License for more details.
15	*
16	* You should have received a copy of the GNU General Public License
17	* along with this program; if not, write to the Free Software
18	* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
19	*/
20
21	//---PACKAGE DECLARATION---
22	package uk.org.iscream.cms.server.filter;
23
24	//---IMPORTS---
25	import uk.org.iscream.cms.server.util.*;
26	import uk.org.iscream.cms.server.core.*;
27	import uk.org.iscream.cms.server.componentmanager.*;
28	import java.util.Random;
29	import java.util.HashMap;
30
31	/**
32	* Acts as a store and checking mechanism for host keys.
33	*
34	* @author $Author: tdb $
35	* @version $Id: KeyManager.java,v 1.3 2002/05/18 18:16:02 tdb Exp $
36	*/
37	public class KeyManager {
38
39	//---FINAL ATTRIBUTES---
40
41	/**
42	* The current CVS revision of this class
43	*/
44	public final String REVISION = "$Revision: 1.3 $";
45
46	/**
47	* The set of characters to be used for our keys
48	*/
49	private final char[] KEYSET = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789".toCharArray();
50
51	/**
52	* Default key length
53	*/
54	public static final int DEFKEYLEN = 15;
55
56	//---STATIC METHODS---
57
58	/**
59	* Return a reference to the single class.
60	* Construct it if it does not already exist, otherwise just return the reference.
61	*/
62	public synchronized static KeyManager getInstance() {
63	if (_instance == null){
64	_instance = new KeyManager();
65	}
66	return _instance;
67	}
68
69	//---CONSTRUCTORS---
70
71	/**
72	* Private constructor to avoid external construction.
73	*/
74	private KeyManager() {
75	try {
76	String keylen = ConfigurationProxy.getInstance().getProperty("Filter." + FilterMain.NAME, "Filter.KeyLength");
77	_keylen = Integer.parseInt(keylen);
78	}
79	catch (PropertyNotFoundException e) {
80	_keylen = DEFKEYLEN;
81	_logger.write(toString(), Logger.WARNING, "No key length found, using default of " +_keylen+ " : " + e);
82	}
83	catch (NumberFormatException e) {
84	_keylen = DEFKEYLEN;
85	_logger.write(toString(), Logger.WARNING, "Malformed key length found, using default of " +_keylen+ " : " + e);
86	}
87	}
88
89	//---PUBLIC METHODS---
90
91	/**
92	* Add or replace a key.
93	*
94	* @param host the hostname to add a key for
95	* @param key the key to add
96	*/
97	public synchronized void addKey(String host, String key) {
98	_keys.put(host, key);
99	}
100
101	/**
102	* Check if a given key is currently valid.
103	* Will respond negatively if the key doesn't match,
104	* or if no key is found (and EnforceHostAuth is on).
105	*
106	* @param host the hostname to check the key for
107	* @param key the key to check
108	* @return whether the check was successful
109	*/
110	public synchronized boolean checkKey(String host, String key) {
111	Object o = _keys.get(host);
112	if(o != null) {
113	// if our key isn't null, we want to make
114	// sure it matches that given
115	String ourKey = (String) o;
116	return ourKey.equals(key);
117	}
118	else {
119	// default to enforcing host auth
120	boolean enforceHostAuth = true;
121	try {
122	// try to get see what's in the config
123	String enforce = ConfigurationProxy.getInstance().getProperty("Filter." + FilterMain.NAME, "Filter.EnforceHostAuth");
124	enforceHostAuth = (Integer.parseInt(enforce) == 1);
125	}
126	catch(PropertyNotFoundException e) {
127	// if it's not set, not enforced
128	_logger.write(toString(), Logger.WARNING, "EnforceHostAuth property not found: " + e);
129	enforceHostAuth = false;
130	}
131	catch(NumberFormatException e) {
132	// if it's not a number, not enforced
133	_logger.write(toString(), Logger.WARNING, "EnforceHostAuth property malformed: " + e);
134	enforceHostAuth = false;
135	}
136	// if enforceHostAuth is true we want to fail the check
137	// and vice-versa
138	return !enforceHostAuth;
139	}
140	}
141
142	/**
143	* Generate a random key with length KEYLEN.
144	*
145	* @return a random key as a String
146	*/
147	public String genKey() {
148	Random r = new Random();
149	StringBuffer s = new StringBuffer();
150	for(int i=0; i < _keylen; i++) {
151	s.append(KEYSET[r.nextInt(KEYSET.length)]);
152	}
153	return s.toString();
154	}
155
156	/**
157	* Overrides the {@link java.lang.Object#toString() Object.toString()}
158	* method to provide clean logging (every class should have this).
159	*
160	* This uses the uk.org.iscream.cms.server.util.NameFormat class
161	* to format the toString()
162	*
163	* @return the name of this class and its CVS revision
164	*/
165	public String toString() {
166	return FormatName.getName(
167	_name,
168	getClass().getName(),
169	REVISION);
170	}
171
172	//---PRIVATE METHODS---
173
174	//---ACCESSOR/MUTATOR METHODS---
175
176	//---ATTRIBUTES---
177
178	/**
179	* This holds the current keys for
180	* the hosts we're authenticating
181	*/
182	private HashMap _keys = new HashMap();
183
184	/**
185	* The length of our keys
186	*/
187	private int _keylen;
188
189	/**
190	* This holds a reference to the
191	* system logger that is being used.
192	*/
193	private Logger _logger = ReferenceManager.getInstance().getLogger();
194
195	/**
196	* This is the friendly identifier of the
197	* component this class is running in.
198	* eg, a Filter may be called "filter1",
199	* If this class does not have an owning
200	* component, a name from the configuration
201	* can be placed here. This name could also
202	* be changed to null for utility classes.
203	*/
204	private String _name = FilterMain.NAME;
205
206	//---STATIC ATTRIBUTES---
207
208	/**
209	* A reference to the single instance of this class
210	*/
211	private static KeyManager _instance;
212
213	}